In an opinion released Wednesday, board members wrote that they believe the acceptance of tickets to 1st Mariner was permitted under a contract with the venue, but said they were "troubled" by the way the tickets have been distributed. Rawlings-Blake got dozens of tickets to distribute to sold-out concerts.

The panel called on the administration to develop a list of "legitimate city purposes" for which the tickets could be used. Rawlings-Blake's office says it has developed new guidelines that would meet that requirement while continuing to allow friends and family to attend events free of charge.

The board launched an inquiry into the matter in September, citing concerns after The Baltimore Sun reported that Rawlings-Blake's office received hundreds of tickets each year to events at the city-owned arena.

The mayor — accompanied by relatives and top aides — used the free tickets to attend several sold-out concerts, including those featuring Rihanna and Jay-Z.

For instance, the mayor's office received 34 tickets to last year's sold-out Sade concert, which kicked off the reclusive musician's first North American tour in a decade, city records show. Rawlings-Blake got 10 of those tickets to distribute at her discretion, top aide Kaliope Parthemos received four and others in the mayor's office claimed a total of six tickets. Six more tickets went to other elected officials who were not identified in the documents, and six went to unnamed community members.

"The logs that purported to track [ticket] distribution were not maintained in a way that allowed the Board to discern precisely who ultimately used the property or what legitimate City purpose was served by its distribution," the opinion states. "It is not possible to determine whether or not a particular distribution served a city purpose or instead represented an improper use of an official's position for the private gain of themselves."

Board members said they could not tell whether anyone had violated ethics rules, but believed any wrongdoing would have been inadvertent. The report pointed out that past administrations have also received scores of free tickets to the arena.

Still, the board said, it is important to develop better accounting of the tickets in order to avoid any appearance of impropriety.

Linda B. "Lu" Pierson, chairwoman of the ethics board, said the panel's opinion should apply to all city agencies that get free tickets to events. City officials also have access to tickets for Pier Six, M&T Bank Stadium, Oriole Park at Camden Yards and other venues.

Pierson said the board was concerned by what it perceived as poor record-keeping by city officials, including an inability to find the contract that governs the city's relationship with 1st Mariner Arena.

"We did find that troubling," she said. The board based its opinion on an old contract, written in 1988, and believes the same provisions still apply.

Ryan O'Doherty, a spokesman for Rawlings-Blake, said the administration was pleased by the report, which he said shows the tickets were "lawfully provided and justified." He said the administration has developed a list of acceptable reasons to distribute the tickets, which will be in effect starting Jan. 1.

But government watchdog group Common Cause expressed concern about the list, which includes a provision to allow "the Mayor and friends and family with the reasonable opportunity to attend the ticketed events in support of a given venue."

"They're missing the point," said James Browning, the director of Common Cause's Mid-Atlantic division. "The pattern of giveaways to relative and supporters is part of the problem. If they're really going to claim that perks for family and supporters are city purposes, how are they going to prove an economic or civic benefit in that?"

Even so, Browning said the ethics board's opinion was a step in the right direction.

"It's a good decision that puts the focus on the fact that the use of these tickets should be accounted for in the same way as other city resources," he said.

Pierson said she was glad to learn City Hall planned to set criteria for awarding tickets, and didn't see an issue with the mayor giving passes to some events to friends and family.

"I think it's a legitimate city purpose for the mayor to attend an event with her family," Pierson said.

The mayor's office suspended distribution of the tickets in September while awaiting the results of the ethics board's investigation, O'Doherty said. The administration will resume accepting and distributing tickets under new guidelines, which will govern distribution offree tickets to 1st Mariner and other major venues.

The guidelines permit distributing tickets for six reasons, including: to serve as a thank-you to community leaders; as goodwill offerings for economic development; to reward city officials and employees and their families for good work; and to provide the mayor, friends and family with "reasonable opportunity" to attend the events to support the venue.

The mayor's office has said that previous mayors also attended arena events at no charge under the terms of the city's agreement with arena operators. Officials said the mayor's office often donates tickets to events, including Baltimore Blast soccer games and the circus, to children and community groups. O'Doherty has said there is "zero evidence that any part of this is new or out of the ordinary."

The mayor has used the tickets to attend high-profile concerts with friends and family. For instance, Rawlings-Blake accepted four tickets in May to see 1980s boy band New Edition. Top aide Kimberly Washington received four tickets, and Teminka Rawlings, the mayor's sister-in-law, received two. Other city officials and state Sen. Nathaniel McFadden also attended the show as guests of the mayor, according to city records.

In another example, Rawlings-Blake's husband, Kent Blake, obtained six tickets from City Hall to see pop star Rihanna in concert in June of 2011. Teminka Rawlings received two tickets, as did then-Mayor Adrian Fenty of the District of Columbia. At least nine other tickets went to the mayor's top aides.

In one instance — a Jay-Z concert — the mayor's office received more tickets than the 35 permitted by the contract, records show.

Rawlings-Blake's use of free tickets became the subject of public debate after she took back Ravens tickets this year for the mayor's skybox at M&T Bank Stadium from City Council President Bernard C. "Jack" Young. He had criticized her support of the Baltimore Grand Prix.

In its opinion Wednesday, the ethics board acknowledged that past administrations have accepted and distributed free tickets from 1st Mariner. That long-standing practice convinced the board that "any Ethics violations that may have occurred were inadvertent rather than intentional," board members wrote.

Rawlings-Blake's law office has said it can't find the current contract that it has argued allows her to accept free 1st Mariner Arena tickets, but does have an older, 1988 version of the agreement with the arena that permits the behavior. The 1988 agreement permitted 1st Mariner to award 35 free tickets to the mayor per event, as available.

In a letter submitted to the ethics board, 1st Mariner General Manager Frank Remesch said Rawlings-Blake had used fewer free tickets than previous administrations.

"It has always been the practice to provide the mayor's office with a small portion of complimentary tickets when available," Remesch wrote. "Due to the ever-changing climate, the current administration has received fewer complimentary tickets than the prior administrations."

The 1988 agreement, signed during former Mayor Kurt L. Schmoke's administration, provided for other free ticket provisions, including requiring the management to honor 30 "lifetime gold passes" and 33 transferable passes to the arena. The contract said the mayor would select recipients if the passes were transferred or expired.

O'Doherty said a new contract for operation of 1st Mariner Arena is expected to be approved next week. He said it will include "essentially the same ticket provision," referring to the 35 free passes.